1. Field of the Invention
The present invention relates generally to a computer implemented method, apparatus, and computer usable program code for navigating in a virtual universe. More specifically, the present invention relates to tabbed controls in a user interface to permit teleporting between virtual universe locations.
2. Description of the Related Art
Modern uses of networked computers leverage the graphics processing power of client computers. The client computer is a computer typically assigned the task of supporting user input and displaying output to a user. Many users reach online environments called virtual universes by using a client computer. A virtual universe permits a user to adopt an avatar or a graphical representation of the user. The user has the power to move the avatar, have the avatar interact with objects, and have the avatar interact with the avatars of other users.
A virtual universe depends on a coordinate system to create anchor points where avatars and objects may be located for purposes of rendering the avatars and objects to each user's computer. Coordinates are two or more units that define a position in a virtual universe. The coordinates may be a Cartesian set of points that define planes and altitudes, however, global coordinates are also known to be used. Typically, an object has a location referenced by a triplet of numbers, and optionally a region or other descriptor of a subset of space within the virtual universe.
In addition to a location, proper rendering of an object or avatar may depend on an orientation or attitude of the object or avatar. An attitude is an overall orientation of an object or avatar in relation to a plane or a vector. For example, an attitude may be based on a number of degrees that an object is offset from a positive direction along a coordinate axis. For virtual universes that form analogs to a real world, north and south compass points may correspond to a positive direction along a first axis and a negative direction along the axis. East and west may be represented in a similar manner, along a second axis perpendicular to the first axis. A third axis may correspond to height. Attitudes may also include offsets of inclination above a plane.
Some virtual universes are organized to present an avatar within a three dimensional environment. Such virtual universes may provide a “first person point of view.” Within a first person point of view, a client computer renders scenery to a two dimensional screen to produce a three dimensional illusion or effect. An example of a three dimensional illusion includes diminishing the size of an object as the object becomes relatively distant from the avatar's position in the virtual world. Another example of a three dimensional illusion is displaying a nearer object as obscuring a more distant object. Each of these illusions is controlled by rendering rules. Rendering rules are a set of rules or steps that a client computer executes to display the two-dimensional image such that the display provides impressions of depth that users expect to see in real life scenery.
Many virtual universes provide a user a teleport feature that permits a user to change an avatar location. The changed location causes a perspective of the avatar to change, and thus changes a screen image of the virtual universe. The perspective may cause objects to be rendered to show the objects at different orientations and distances from the avatar. The perspective may cause formerly rendered objects to be obscured by other objects. Likewise, the perspective may cause formerly rendered objects to be so distant that the objects are not rendered in the second perspective. In this case, a client computer renders a new set of objects to the user's computer display screen.
FIGS. 1A and 1B show a teleportation which results in objects being positioned at different orientations and distances relative to the avatar. An avatar 101 at a first location has a first perspective bounded by left side 103 and right side 105. Left side 103 may correspond to a left-most edge of a window, display, or other limitation on a user's client computer. Similarly, right side 105 may correspond to a right-most edge of a window, display, or other limitation on a user's client computer. Between left side 103 and right side 105, some objects may be located. To the extent that rules of rendering are met (atmospheric effects and intervening surfaces), a client computer may display two objects which represent aspects of cube 107 and sphere 109.
FIG. 1B shows the effect of teleportation or other movement from a former location 110 to teleported location 111. The avatar now sees cube 107 nearby obscuring sphere 109. The avatar's perspective changes because the location and attitude of the avatar change.
Teleporting permits a user to see much of a virtual world quickly. Unfortunately, the user may have no graphical data concerning a past teleport source location. As a result, the user may not adequately understand the content of virtual objects near to a prior location.
Thus, a need exists to provide a user with better visual indications of past presence, or future predictions of presence, at a location in a virtual universe.